Range-finder, three-dimensional measuring method and light source apparatus
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKenya Uomori, Atsushi Morimura, Joji Wada, Takeo Azuma
Life of this patent
Estimating the term…
Abstract
The invention provides a range finder capable of carrying out three-dimensional measurement stably for a long period of time. A light pattern is projected on a subject by using a light source array unit in which a plurality of light sources, such as LEDs, are arranged. Even when each LED has a small light quantity, a sufficiently large quantity of light can be projected on the subject by the entire light source array unit, and hence, the three-dimensional measurement can be stably carried out. Also, a plurality of light patterns can be generated by electrically controlling a light emitting state of each LED of the light source array unit.
Claims20
A range finder for measuring a three-dimensional position of a subject by projecting light on said subject and receiving reflected light, comprising:
- a light source array unit in which a plurality of light sources are arranged;
- and
- a light source control unit for allowing at least two kinds of light patterns to be projected from said light source array unit by controlling a light emitting state of each of said plurality of light sources of said light source array unit.
A method for measuring a three-dimensional position of a subject based on reflected light images respectively obtained with at least two kinds of light patterns projected on said subject, comprising the steps of:
- storing a parameter of an equation for approximating a space locus having a constant light intensity ratio between said two kinds of light patterns before three-dimensional measurement;
- obtaining a brightness ratio of a target pixel on the basis of reflected light images respectively obtained with said two kinds of light patterns projected;
- and
- carrying out the three-dimensional measurement by using said brightness ratio of said target pixel and said parameter of the space locus.
A method for measuring a three-dimensional position of a subject based on reflected light images respectively obtained with at least two kinds of light patterns projected on said subject, comprising the steps of:
- storing a plurality of luminance ratio images in each of which a light intensity ratio between said two kinds of light patterns is expressed on a plane with a different fixed depth value before three-dimensional measurement;
- obtaining a brightness ratio of a target pixel based on reflected light images respectively obtained with said two kinds of light patterns projected;
- and
- carrying out the three-dimensional measurement by comparing said brightness ratio of said target pixel with a light intensity ratio in the vicinity of coordinates of said target pixel on each of said luminance ratio images.
A method for measuring a three-dimensional position of a subject based on reflected light images respectively obtained with at least two kinds of light patterns projected on said subject, comprising the steps of:
- storing a plurality of luminance ration images in each of which a light intensity ratio between said two kinds of light patterns is expressed on a plane with a different fixed depth value before three-dimensional measurement;
- setting representative points on each of said luminance ratio images and determining a parameter of a relational expression between a light intensity ratio and a depth value of each of said representative points on the basis of said plurality of luminance ratio images and said different depth values respectively corresponding to said luminance ratio images;
- obtaining a light intensity ratio of a target pixel based on reflected light images respectively obtained with said two kinds of light patterns projected;
- and
- carrying out the three-dimensional measurement by using coordinate values of said target pixel, said light intensity ratio of said target pixel and said parameter of said relational expression between the light intensity ratio and the depth value of each of said representative points.
A range finder for measuring a three-dimensional position of a subject by projecting light on said subject and receiving reflected light, comprising:
- a projection unit for projecting at least two kinds of light patterns;
- and
- a projected light pattern control unit for making a measurement range or measurement accuracy variable by changing a set of light patterns to be projected from said projection unit.
Dependencies are inferred from the claim text.